WASHINGTON — At an early learning center in Eatonville, Wash., today, mourners will light candles to honor Margaret Anderson, the 34-year-old ranger and mother of two toddlers who was shot and killed on New Year's Day while she tried to set up a roadblock in Mount Rainier National Park.

That same evening, at the mall of the University of Arizona in her hometown of Tucson, Democratic Rep. Gabrielle Giffords will hold a glow stick and listen to a symphony orchestra at a vigil to recognize the one-year anniversary of the shooting that critically wounded her and killed six others.

In ceremonies from New York to Seattle, candlelight vigils are planned in more than 30 cities to remember the thousands of Americans who are murdered in the United States each year, most of them with guns. For gun-control advocates, it will be a day to "light a candle against the darkness of gun violence" and to demand that Congress tighten the nation's gun laws.

Congress did nothing of the sort after the Giffords shooting last year, and the odds are good that nothing will happen this year.

Democratic Rep. Norm Dicks of Washington state, a gun-control proponent who gets failing grades from the National Rifle Association, said it's just a matter of political reality on Capitol Hill. He wants Congress to overturn a law that took effect in 2010 that allows loaded guns in national parks, but he's not optimistic.

"The problem is the NRA's got a majority in the House and Senate — that's the reality of it," said Dicks, an 18th-term congressman.

John Velleco, director of federal affairs for the Virginia-based Gun Owners of America, said that Congress should instead loosen existing gun-control laws to make it easier for citizens to defend themselves.

"I think the vigils completely miss the point because they're assuming that more gun-control laws will lead to fewer crimes, but we find that the opposite is true," he said. "The more gun-control laws you have, the easier it is for criminals to commit crimes."